Low-latency video applications such as virtual reality (VR) are difficult to stream over wireless data networks (e.g., Institute of Electrical and Electronics Engineers (IEEE) 802.11 family of standards often known as Wi-Fi® (hereinafter, Wi-Fi), because of the congestion of 5 and 2.4 GHz bands. Radar channels (DFS) within the 5 GHz band are less congested, enabling a Wi-Fi access point (AP) or a host computer running a VR app to switch the connected Wi-Fi client (e.g., a head-mounted device (HMD)) to a radar channel and achieve better performance. Due to regulatory requirements on usage of DFS channels and non-preemption requirements for high priority devices such as military or police devices, difficulties in using the radar channels often arise.
Current use of radar channels is incompatible with virtual reality. When radar use is detected in the same channel as a device, the device is allowed a maximum of 200 ms to vacate the channel and move to another one. The typical time to switch channels is 100 ms, which may go up to 1.5 seconds on some implementations. For VR applications, a user would experience stalling of the VR experience during the switching time, leading to unacceptable user experience and essentially renders wireless VR unusable in these bands.
Other requirements of using radar channels require use of a radar detector to continuously scan radar channels intended to be used. A DFS channel may be determined to be usable only after scanning for a minimum of one minute (and detecting no other devices on the channel). When a device is forced to vacate a DES channel (e.g., due to detected use by another device on the radar channel), the device must move to a congested (non-DES) channel for at least one minute. While on the congested channel, the user may experience intermittent freezes in the VR experience, which makes wireless VR unusable.
Errors such as latency, missing frames, or poor user experience may have a disproportionate effect on VR due to the nature of the VR experience, even when the issues are momentary. Users may experience nausea, disorientation, or lose emersion in the virtual reality, with any of the errors above. These results may cause users to become dissatisfied with VR, temporarily stop using VR, or not use VR altogether.